1. Field of the Invention
The present invention relates to surgical orthopedic implants and methods of manufacturing same. Even more particularly, the present invention relates to an improved orthopedic joint implant component (e.g. femoral component) having a non articulating surface that fastens the implant to the patient's bone tissue adjacent the joint to be replaced and an articulating surface that engages a corresponding implant member (e.g. tibial component) and wherein the articulating surface is dressed using a programmable CNC multi-axis grinder that cuts multiple parallel grooves in the articulating surface of a blank (e.g. cast, forged, machined) as the blank is oscillated about a first axis on a fixture and translated during such oscillation to define the shape of the articular surface being cut, subsequent method steps including a coarse polishing to remove "peaks" formed by the grinder, followed by a fine polishing of the articular surface.
2. General Background
Prosthetic joint devices are well known in the art. One of the most common types of joint prosthetic devices is a knee prosthesis that includes a femoral component and a tibial component. The femoral component typically has a "J" shape and includes a distal articulating surface with anterior, distal and posterior condylar portions. The non-articulating surface of the prosthesis includes a number of flat intersecting surfaces that mate with similarly shaped surfaces surgically formed on the patient's distal femur.
One of the problems that has plagued the manufacture of femoral knee implants is that of proper sizing and shaping. The distal femoral articulating surface is a complex structure. In the past, sizing and shaping this structure has been a highly labor intensive process that requires a number of manual polishing steps. However, these polishing steps are typically performed by workers that do not exactly duplicate the same shape each time. Variations can occur even at the same factory between two different workers.